Teleconferencing, the use of video and sound to connect two or more locations, permits groups of people at a distant location to see and hear a presenter at another location. A presenter from a remote location will typically be combined with graphics using a split screen technique or dual monitors.
Rear projection, and large liquid crystal display screens, have been used to combine the presenter with graphics. The audience in the same room with the presenter, in front of the rear projection or liquid crystal display, is seeing first generation graphics, but when photographed and transmitted to another location, it must be projected again which makes it second generation. Because of the loss of two generations, the graphic data at the distant location is degraded to a point where many graphs, charts and text cannot be clearly read.
Combining the presenter with the graphics using front projection suffers from the additional problems of blinding the presenter, and distorting the graphics his body intercepts, which is disconcerting to the viewers.
In teleconferencing, there are numerous variations in the techniques for combining a presenter and the selected graphics. None of these techniques can be considered ideal. The effort to place the presenter in front of the projected graphics is to improve personal contact between a presenter and his audience, as compared to the sleep inducing graphics image with an off-screen presenter.
The Interactive Teleconferencing Display System uses equipment performing identical functions at each location thus permitting any location to originate or participate in a conference. The equipment includes a front or rear projection screen, an electronic projector, and a signal processor. When the presenter is in front of a front projection screen, a matte signal is generated that selectively inhibits the projector to prevent the projected graphics from illuminating the presenter. The graphics are downloaded and stored at all locations. The presenter, having been extracted by a matte signal is transmitted to all locations where it is matted over the graphics before projection. By separately transmitting the graphics image and the presenter""s image, and combining them at the remote location, each is an original and there is no loss of detail when displayed.
An individual at another location may participate at any time by stepping in front of his screen. All locations will see and hear both the presenter and the additional participant. Both participants may look at each other, point to, and discuss the material being displayed. They may also look toward their local audience without being blinded by the projector. Participants from other locations may join in and also appear on all screens.